During the manufacture of a product that includes two or more components that must be joined to one another to form the final product, difficulties often arise in maintaining the separate components in proper registration with one another until they are joined. An example of a product having separate components joined to one another is a thermal shield of the type used in connection with vehicles and other apparatus, e.g., electrical generators and air compressors, among others, powered by internal combustion engines. This type of thermal shield typically comprises an insulating material, such as fiberglass batting or air, encapsulated between first and second metal plates that are joined to one another by a seam extending around the periphery of the thermal shield.
Thermal shields are conventionally manufactured by die cutting the first and second plates to the desired shape of the finished thermal shield and then stamping at least one of the plates to form a pan having a cavity that receives the insulation. The insulation is then inserted into the cavity, and the first and second plates are joined to one another, typically using a folded or rolled seam at the peripheral edges of the plates. Prior to forming the seam, the first and second plates are brought into registration with one another. Often, however, proper registration is difficult to effect and/or maintain due to the speed of the manufacturing process used to make the thermal shield or is destroyed during the folding or rolling of the seam. Results of misregistration of the first and second plates range from acceptable, but unsightly, seams to severely malformed seams that require the manufacturer to scrap the affected thermal shields.